1. Field of the Invention
The present invention relates to an apparatus for impedance matching in a dual standby portable terminal and a method thereof. More particularly, the present invention relates to an apparatus for impedance matching that enables improvement of radiation characteristics by matching the impedance of a module to an optimal value while another module is operating in a communication mode in a dual standby portable terminal providing at least a dual mode, and a method thereof.
2. Description of the Related Art
Over time, portable terminals have gained in both popularity and use. In light of their popularity, as well as user demand, portable terminals providing various additional functions are being developed. One such terminal that has recently come into the market is a dual mode portable terminal. A dual mode terminal uses a communication network that supports one or more radio communication protocols.
In comparison with a dual mode terminal, a conventional dedicated terminal, which supports only one radio communication system, can communicate with another terminal only in a service area of the corresponding radio communication system. However, with a dual mode portable terminal, for example a terminal that supports both a Code Division Multiple Access (CDMA) system and a Global System for Mobile Communications (GSM) system, the terminal can communicate with another terminal in either a CDMA or a GSM service area. Accordingly, the usability of the terminal is expanded.
In a conventional dual mode portable terminal, changing the terminal from one mode to another mode is complicated and requires time. For example, the system mode change may be executed using a menu selection after booting the portable terminal and entering an idle mode, all of which requires time and is an inconvenience for the user. To solve such inconvenience, a dual standby portable terminal that can simultaneously support two modes, for example both GSM and CDMA, has been suggested. In the dual standby portable terminal, a second call may be newly received by automatically changing a mode while a first call is being conducted.
A dual standby portable terminal having more than one mode generally has an antenna corresponding to each mode. Additionally, while executing one communication mode, the dual standby portable terminal continues to operate the other mode. Therefore, a problem of deteriorating radiation characteristics and reception sensitivity of an antenna in a communication mode may arise due to interference between the two antennas of the corresponding modes.